Its just libido matching. A 15 year old male and a 25 year old female. Perfectly matched.
I’m not buying it. Attractive ladies in their 20’s who just want sex can pick up any 18 year old guy anywhere, anytime. All they have to do is whistle. There is something going on with teachers preying on students. It has to be a control thing. She has all the power. So it is a power trip for her to be completely in control over a man.